Senior Full-Stack Engineer (Fintech, Trading and Banking)

About the Company

Our client is a financial technology services provider dedicated to expanding global access to digital assets by building innovative solutions in the trading ecosystem. Their products provide exchanges, liquidity solutions, and enterprise-grade integrations for clients worldwide. We are currently undertaking a massive project to integrate our core trading infrastructure into the ecosystem of a major bank, and we are looking for a highly capable Senior Full-Stack Engineer (Web & Backend) to drive this initiative.

In this role, you will be responsible for the end-to-end development and integration of high-load trading components, working directly with our CTO and the bank’s technical leadership team.

What You'll Do

• Infrastructure Integration: Design and implement secure, scalable integrations bridging our trading engine with the existing architecture of a large institutional bank.

• Full-Stack Development: Build and maintain high-performance server-side services and responsive web interfaces for complex financial operations.

• High-Load Engineering: Optimize services for low latency, multi-threaded data processing, and real-time streaming protocols (WebSockets).

• Technical Communication: Collaborate directly with the bank’s tech leads, architects, and our CTO to align on architectural decisions, APIs, and strict security protocols.

• Engineering Standards: Write clean, reliable, and testable code, conduct rigorous code reviews, and help define architectural best practices.

AI-Native Approach (Strict Requirement)

Fluency in and active application of AI tools is a strict filter for this role. We are looking for an engineer whose daily development cycle is organically intertwined with AI assistants and agentic workflows:

• Regular, hands-on use of modern tools (e.g., Claude Code, Cursor, MCP servers, GitHub Copilot) for code generation, architectural analysis, debugging, and routine automation.

• Proven ability to significantly increase delivery speed and quality using AI tools without sacrificing code reliability or security.

Who You Are

• You have deep domain knowledge in fintech, trading, banking, payment gateways, or exchange platforms.

• You possess a proven track record of building distributed, high-load systems with stringent fault-tolerance and security requirements.

• Strong Communicator: You can confidently defend architectural decisions on a technical level in front of C-level executives and enterprise banking teams.

• Fast Learner: You are ready to dive deep into the architecture and business logic of our existing products, supported by our team's mentorship and onboarding.

Qualifications

• English: Upper-Intermediate or Fluent (confident in leading technical negotiations and writing documentation).

• Experience: 5+ years of commercial development experience as a Full-Stack or Senior Backend Engineer.

• Backend Stack: Deep knowledge of server-side technologies: Node.js/TypeScript, RESTful API design, WebSockets, and message queues.

• Frontend Stack: Strong command of the modern web stack (React.js, TypeScript, state management) for building data-heavy interfaces.

• Data & Infrastructure: Experience with relational databases, complex SQL optimization, CI/CD pipelines, and containerization.

Bonus Points:

• Experience integrating with core banking systems, FIX protocols, or financial institution Open APIs.

• Understanding of market mechanics, liquidity, and order books.

We Offer

• Flexibility & Hubs: Flexible working hours with physical office access in Poland (Wroclaw) and Ukraine.

• Health & Wellness: Medical Insurance in Ukraine and a Multisport program in Poland.

• Time Off: Paid vacation, sick leaves, and all official holidays.

• Growth: Access to educational programs and corporate English classes up to three times a week.

• Equipment: Top-tier hardware and development gear provided.

• Contractor Support: Complete tax and accounting services handled for Ukrainian contractors.

• Culture: Regular team-building, tech events, and an advanced bonus system.